SLASF21 December   2022 AFE78101 , AFE88101

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information
    5. 6.5  Electrical Characteristics
    6. 6.6  Timing Requirements
    7. 6.7  Timing Diagrams
    8. 6.8  Typical Characteristics: VOUT DAC
    9. 6.9  Typical Characteristics: ADC
    10. 6.10 Typical Characteristics: Reference
    11. 6.11 Typical Characteristics: Power Supply
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Digital-to-Analog Converter (DAC) Overview
        1. 7.3.1.1 DAC Resistor String
        2. 7.3.1.2 DAC Buffer Amplifier
        3. 7.3.1.3 DAC Transfer Function
        4. 7.3.1.4 DAC Gain and Offset Calibration
        5. 7.3.1.5 Programmable Slew Rate
        6. 7.3.1.6 DAC Register Structure and CLEAR State
      2. 7.3.2 Analog-to-Digital Converter (ADC) Overview
        1. 7.3.2.1 ADC Operation
        2. 7.3.2.2 ADC Custom Channel Sequencer
        3. 7.3.2.3 ADC Synchronization
        4. 7.3.2.4 ADC Offset Calibration
        5. 7.3.2.5 External Monitoring Inputs
        6. 7.3.2.6 Temperature Sensor
        7. 7.3.2.7 Self-Diagnostic Multiplexer
        8. 7.3.2.8 ADC Bypass
      3. 7.3.3 Programmable Out-of-Range Alarms
        1. 7.3.3.1 Alarm Action Configuration Register
        2. 7.3.3.2 Alarm Voltage Generator
        3. 7.3.3.3 Temperature Sensor Alarm Function
        4. 7.3.3.4 Internal Reference Alarm Function
        5. 7.3.3.5 ADC Alarm Function
        6. 7.3.3.6 Fault Detection
      4. 7.3.4 IRQ
      5. 7.3.5 Internal Reference
      6. 7.3.6 Integrated Precision Oscillator
      7. 7.3.7 One-Time Programmable (OTP) Memory
    4. 7.4 Device Functional Modes
      1. 7.4.1 DAC Power-Down Mode
      2. 7.4.2 Reset
    5. 7.5 Programming
      1. 7.5.1 Communication Setup
        1. 7.5.1.1 SPI Mode
        2. 7.5.1.2 UART Mode
      2. 7.5.2 Serial Peripheral Interface (SPI)
        1. 7.5.2.1 SPI Frame Definition
        2. 7.5.2.2 SPI Read and Write
        3. 7.5.2.3 Frame Error Checking
        4. 7.5.2.4 Synchronization
      3. 7.5.3 UART
        1. 7.5.3.1 UART Break Mode (UBM)
      4. 7.5.4 Status Bits
      5. 7.5.5 Watchdog Timer
    6. 7.6 Register Maps
      1. 7.6.1 AFEx8101 Registers
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Multichannel Configuration
    2. 8.2 Typical Application
      1. 8.2.1 4-mA to 20-mA Current Transmitter
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Start-Up Circuit
          2. 8.2.1.2.2 Current Loop Control
          3. 8.2.1.2.3 Input Protection and Rectification
          4. 8.2.1.2.4 System Current Budget
        3. 8.2.1.3 Application Curves
    3. 8.3 Initialization Set Up
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
  9. 9 Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  10. 10Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.3 Initialization Set Up

This section describes several recommendations to set up the AFEx8101.

The AFEx8101 power up with the CRC enabled. If the device is intended to be run without the CRC, the CRC must be disabled by setting the CRC_EN bit to 0h in the CONFIG register. Be aware that the command to write to this register is first done with the CRC enabled. The CRC byte must be appended to the command for the device to interpret the command correctly. To disable the CRC after start up, write 0x02 0x00 0x26 0x24 to the device. The first three bytes write the command, while the last byte is the CRC byte. For more information on the CRC, see the communication description in Section 7.5.2.3.

The AFEx8101 also power up with the SDO pin disabled. The SDO is required for reading from any of the device registers, as well as reading any data from the ADC in SPI mode. The SDO is enabled by writing 0h into the DSDO bit in the CONFIG register. See also Section 7.5.2.1 and Section 7.5.2.2.

To enable the ADC, first enable the ADC buffer by writing 0h into the BUF_PD bit in the ADC_CFG register. Information about using the ADC in different modes of operation is in Section 7.3.2.